Generally, when producing mixed beverages, it is necessary to first degas the liquid's base component, which is often water, and to then mix it with at least one additive, such as a flavoring or a syrup, to a required end concentration. If the mixed beverage is a carbonated beverage, it will also be necessary to carbonate and buffer the mixed beverage with CO2 gas until it has been filled into containers or bottles. Such mixed products are processed in mixing systems, often called mixers, consisting of several components.
Two known ways to degas a base component are vacuum degassing, and pressure degassing. Both kinds of degassing can be single-stage or multi-stage. During vacuum degassing, the partial pressure drop that releases dissolved gases from the base component is achieved by vacuum or pressure drop. During pressure degassing, the release of the dissolved foreign gases from the particular base component is achieved by diffusion in a carrier gas free from oxygen and/or nitrogen, e.g. CO2 gas.
The mixing of the base component with the at least one additive (for example syrup) into the finished or mixed product is currently performed via ratio control, i.e. by controlling the volume flows of the base component and of the additive so that they maintain respective set points. Both set points are put into a ratio according to the preselected or desired formulation. To achieve the required dosing accuracies, continuous control of the volume flows, in particular continuous volume flows through the particular mixing chamber, will be required.
The carbonation or dosing of the CO2 gas, for known methods and mixing systems, will also be performed via ratio dosing or via spray carbonation. In the latter case, the mixed product is sprayed into a container that has been pressurized with CO2 gas. The gas pressure is set according to the saturation pressure, which depends on, among other things, the dosing rate and the temperature. The CO2 gas dissolves in the mixed product until a balance is achieved between the pressure of the CO2 gas in the atmosphere and the partial pressure or saturation pressure of CO2 gas in the carbonated mixed beverage.
A filler usually fills a container or bottle with the carbonated mixed product or mixed beverage produced with the mixing system. Like the mixing system, the filler is a component part of one complete filling line.
In known systems, continuous operation is required to assure accuracy in dosing, mixing, and carbonation. Unfortunately, disruptions in continuous operation are almost inevitable. These disruptions include disruptions in the environment, in the system, and in the packaging material, for example disruptions arising from bottle breakage etc. As a result, stops or reduced output will often occur.
To accommodate these interruptions, known systems require a large volume buffer or buffer tank for uncoupling or buffering between mixing system and filler. Practical buffer tanks have relatively large volumes, for example up to 1000 liters. Usually, such buffer tanks are operated with a heavily fluctuating fill level. This means that the mixed product in the buffer tank must be overlaid with a CO2 gas cushion whose pressure is higher than the CO2 saturation pressure in the mixed product. In case of changing fill levels, it will be necessary to replenish the buffer tank with CO2 gas or to drain it. This leads to high consumption of CO2 gas.
A device and a method for producing mixed products were introduced by DE 1 213 212. Consequently, this publication provides for the base component, for example water, and the additive, for example syrup, to be simultaneously fed to a dosing unit, wherein the components enter a mixing vessel at a preset, accurately measured quantity ratio. The disadvantage of this procedure is that known dosing units for the simultaneous feeding of several components are complex and expensive and, moreover, usually only have limited accuracy.